With teams using more than 100 unique apparatuses to launch globular projectiles a half-mile or more, the 27th annual World Championship Punkin Chunkin event is our pick as November’s Weird Festival of the Month.

Hotels are a collecting opportunity for Langdon, a court reporter from Springfield, Mo. “I always take pens and notepads and then use them for work,” she says. “That way, when I’m in a rut and wishing I was someplace else, I can look at my pen and smile about some sweet vacation memory.”

But it doesn’t end there. Unused soaps, shampoos, lotions — all disappear into her carry-on. She lifts packets of ketchup and mustard from room service trays left in the hallway. And, of course, she brings home the hotel key cards.

“Not only do they remind me of where we’ve been,” says Langdon. “But they also make good little scrapers for the side-view mirror of my car. And emergency screwdrivers.”

Maybe you know someone like Langdon. Maybe you are someone like Langdon. Either way, you probably also know that there’s more than ever to collect while you’re on the road, from cheesy T-shirts and coffee mugs to boarding passes and key cards.

What to keep?

Professional organizer Jamie Novak says it’s normal for travelers to pocket a “physical representation” of their vacation. But before they snatch up that porcelain figurine or sombrero, she advises that they remember the acronym CUTE, which stands for “Can’t Use This Ever.” For example, the sombrero is useless (unless you belong to a Mariachi band) but salt-and-pepper shakers might be useful.

“If you feel compelled to bring an item home, try to make it something useful and not CUTE,” she says.

Oh, that’s cute.

Can’t decide what’s worth holding on to? Here’s a helpful list:

THINGS TO TAKE

Boarding passes
These don’t just make nice keepsakes. My travel-writing colleague John DiScala, who writes the blog JohnnyJet, plans to cover a wall in his collection some day. “I also keep them, of course, for mileage purposes — just in case I don’t get credited,” he says.

I’ve written about the airlines’ insistence on being shown an actual boarding pass when you try to collect award miles, particularly on a codeshare flight. Better hold on to those stubs if you need the miles.

Hotel key cards
They’re meant to be kept, they’re collectible, and you’re probably better off pocketing them, too. Karen Finlay, a sales manager for the guidebook Lonely Planet, says she takes her cards, “just as a memento and because I forget to hand them in.”

But it’s probably better that way. I can’t seem to completely debunk the rumor that hotels encode the cards with your personal information. The best way to make sure no one gets the card is to just keep it.

Receipts
Leslie Andrea Westbrook keeps every single one. So do I. That’s because she’s a travel writer, like me. “It’s a tax write-off,” she says.

If you are a business traveler, or part of your vacation is a write-off, you definitely don’t want to throw anything away. Take it from someone who’s been audited by the IRS and was lucky enough to have all the receipts. I shudder to think what might have happened if I didn’t.

Pictures
“They don’t take up any space in your bag, and nothing is worse than trying to travel and having to lug bags around everywhere,” says Colin Wright, a professional traveler, blogger and self-described minimalist.

Actually, he’s on to something. Several professional organizers I spoke with for this story also recommend taking photos when you’re on vacation.

Odds and ends
Sebrina Schultz, a Texas event planner, says she collects anything she finds during her travels. “Rocks, bark from trees, soap boxes, matchstick books, coasters, logo-embossed restaurant napkins, paper menus, travel brochures,” she says. Every six months, she must go through her stashes and do what she calls a “massive purging”. “I usually end up hanging onto a few things,” she adds.

This is classic “pack rat” behavior, and you’ll pay for it when you try to check in for your flight home and find that your bags are overweight.

Items resulting from ‘vacation shopping disorder’
That’s the word used by Mary Carlomagno, an organization expert and author of the book “Secrets of Simplicity.” “We all suffer from it at times,” she says. “We have to buy an Asian ceremonial tea outfit just because we think we will never be in Hong Kong again. But you and I know this is not true.”

For her, it’s a matter of separating yourself from the emotional attachment of that “must–have” merchandise. I’ve traveled with compulsive shoppers, and I know how difficult this can be.

Something you already have back home
“I really don’t need any more college sweatshirts, T-shirts, or coffee mugs,” says Steven Goodman, an educational consultant and frequent traveler. Still, he admits it’s difficult to visit a college and not return with a sweatshirt. “They’ll probably go unworn for some time,” he says, because he already has a formidable collection of sweatshirts, T-shirts and coffee mugs.

Collect only what you can use. Remember — be CUTE.

Something you shouldn’t have
I can’t pass up the opportunity to say something about hoarding and award programs. Two facts can’t be disputed: Award programs benefit the travel company more than they do the traveler, and they lose value over time.

There’s a whole online community of mileage pack rats that forage for deals and award offers online. Some of these travelers are perfectly reasonable and pleasant, while others are rabid elitists. The latter probably shouldn’t be collecting miles. Playing the mileage game brings out the worst qualities in them. They should also be kept away from the computer. But that’s a topic for another time.

Next time you’re on vacation think twice before pocketing that bottle of shampoo, buying the velvet Elvis, or claiming the frequent flier miles. You may be better off without them.

Christopher Elliott is the ombudsman for National Geographic Traveler magazine. You can read more travel tips on his blog, elliott.org or e-mail him at celliott@ngs.org.